亚硝基胍诱变丙酸杆菌选育高产抑菌物质菌株

Screening of Propionibacterium shermanii Strains with High Production Antibacterial Metabolites by NTG Mutation

[目的]提高丙酸杆菌代谢物的抑菌活性,为薛氏丙酸杆菌代谢物的工业化生产奠定基础。[方法]以实验室保藏的薛氏丙酸杆菌H1310为出发菌株,采用亚硝基胍(NTG)进行诱变处理,待突变菌株长出后采用双层平板筛选法进行筛选,而后通过深层液体发酵对筛选到的菌株进行复筛。[结果]当最优的NTG诱变浓度为0.3 mg/m L时,致死率为90.69%。采用双层平板法,从3 564株菌落中挑选出87株突变株,进一步进行复筛,获得一株突变菌株,其代谢物抑菌活性达(28.30±2.47)AU/m L,比出发菌株提高43.87%。[结论]确定了丙酸杆菌NTG诱变选育的试验方法,获得一株抑菌活性高的遗传性能稳定的菌株。

[.Objective] To improve the antibacterial activity of the metaholite of Propionibacterium shermanii and lay a foundation for the indus- trial production of the metabolite. [ Method] This research used Propionibacterium slwrmanii H1310 as the original strain ,through nitrosoguanidine （NTG） mutagenesis ,using the double-layer plate screening method to screen the mutant strains. The strains which were surrounded by clear inhi- bition zone were cultivated and measured the antibacterial activity. [ Result] The optimal concentration of NTG was 0.3 mg/mL,for the lethality rate was 90.69%. 87 strains chosen from 3 564 strains were fermented again. A high antibacterial metabolites stain NTG110605 was selected and its antibacterial activity reached （28.30 ± 2.47） AU/ mL, which was 43.87% higher than the original strain. [ Conclusion ] The experimental methods of mutation breeding of Propionibacterium shermanii is confirmed and a strain which produced more antibacterial substances is obtained.